"All DCPS schools and most charter schools have agreed to a common enrollment lottery that will take effect for school year 2014-15. The new process will cut down on duplicate applications and student reshuffling at the beginning of the year. Why, then, have some charters opted not to participate?

"For years now, observers of the DC education scene have been calling for a unified enrollment process, either for all charter schools or for both charters and DCPS schools. The benefits seem clear: parents will be able to file a single application and rank schools in the order of their preference. Schools will no longer find students leaving in September as they get into other schools off waiting lists, or simply decide they would be happier at another school where they also secured a spot.

"But when the deadline for joining the common lottery arrived at the end of September, a dozen charter schools were missing from the list. The charters who are participating account for nearly 90% of charter slots, but the ones who opted out include some highly sought-after schools, such as Washington Yu Ying and Latin American Montessori Bilingual (LAMB). Clearly, some parents will continue to apply to those schools separately, in addition to or instead of applying through the common process.
...
"Patricia Ragland, the enrollment coordinator at Tree of Life PCS in Ward 5, said the school draws many of its students by word-of-mouth or because their siblings are already enrolled. The school's executive director decided not to participate in the unified lottery because it would have made it easier for families to find other options, Ragland said.
...
"As for LAMB, a Tier 1 school in Ward 4, its Executive Director, Diane Cottman, said in an email that the school is "hesitant to join a system that has not yet been finalized."

"With a more cautious approach," she wrote, "LAMB hopes to avoid the uncertainty that comes with a work in progress."

But, as project manager Bhat points out, DC is not the first city to implement a unified enrollment lottery. Denver and New Orleans have had similar programs in place for several years, and New York has instituted a common application system. And the same company that designed all three of those systems, the Institute for Innovation in Public School Choice, is designing the one in DC. Newark and Philadelphia are also working on plans for common lotteries."

Wednesday, October 30, 2013

"Thirty-two states retain the death penalty in the U.S., but a new obstacle is making it increasingly difficult for them to carry it out. Pharmaceutical companies are taking a moral stand. The manufacturers of the drugs required by state departments of corrections for executions are saying they will not allow their products to be employed in this way. Manufacturers in the UK, US, Denmark, Israel, Switzerland, Germany, Austria, and India have taken steps to prevent their drugs being used in executions.

This has had an astonishing effect. Shortages of lethal injection drugs and attendant litigation have resulted in moratoria—an official halting of executions—in Arkansas, California, Kentucky, Louisiana, Maryland, Missouri, Montana, Nebraska, North Carolina, Oregon, and Tennessee. Historically, state entities do not move directly from having the death penalty to abolition. They begin with a moratorium on killing and then, when the population has grown unused to executions, the death penalty can be abolished. Of the states mentioned above, Maryland abolished the death penalty this year and abolition bills have been put forward in Nebraska, Colorado, and California. California came very close to passing its abolition bill—voting against by 52 to 48. Meanwhile, the media coverage of the issue has exposed the unsavoury details of the execution process and created opportunities for serious debate about abolition."

Summary: One of the main challenges in the current practice of kidney exchange is matching highly sensitized patients. These patients are very unlikely to be compatible with a random donor. Current pools of patient-donor pairs are not too large and they contain many such hard-to-match patients. Therefore, the compatibility graphs associated with these pools are sparse (or sometimes called thin). One way to create a thicker pool is to wait for many pairs to join before matching (finding a set of disjoint exchanges), and a major decision clearinghouses are facing is how often to search for allocations. On one hand, waiting is costly; while patients are waiting, they are on dialysis and their health conditions deteriorate. On the other hand, in the current programs, matching too frequently may reduce the number of matched pairs, especially highly sensitized ones.

In this project, we study this intrinsic tradeoff between the waiting time and the number of matches by analyzing a class of algorithms (which are used in practice) that search periodically for allocations. We perform sensitivity analysis on the amount of waiting given different types of allocations (using 2-ways, 3-ways, or chains). We find that if only 2-way cycles are conducted, in order to gain a significant amount of matches over the online scenario (matching each time a new incompatible pair joins the pool) the waiting period should be very long. If 3-way cycles are also allowed we find regimes in which waiting for a short period also increases the number of matches considerably. Finally, a significant increase of matches can be obtained by using even one non-simultaneous chain while still matching in an online fashion. Our theoretical findings (based on random graph models and motivated by clinical data) and computational experiments (using clinical data from some of the largest exchange programs in the US) lead to policy recommendations.

Monday, October 28, 2013

According to this story in the Stanford Daily there are more freshman seminars this year, but no more applicants than last year.

"Though there was an overall increase in the number of Introductory Seminars (IntroSems) offered this year, the number of applications for and enrollments in fall quarter seminars stayed relatively the same as last year, according to Russell Berman, faculty director of the Stanford Introductory Seminars (SIS) program.

This year, 257 classes are available over the course of three quarters—more than the 221 classes offered last year—some of which are also eligible to fulfill the new Ways of Thinking/Ways of Doing breadth requirement.

“These very popular courses sometimes create a problem for the program insofar as students apply for these and nine out of 10 are going to get turned down,” Berman said. “Sometimes students only apply to those courses that have strong enrollments, and then they get turned down multiple times.”

Berman noted several courses from all disciplines with competitive entries this quarter, including ME26N: Think Like A Designer, taught by Shilajeet Banerjee M.S. ‘00, associate professor of mechanical engineering at the d.school; Psychology Professor Carol Dweck’s PSYCH12N: Self Theories; and ECON26N: Who gets what? The New Economics of Matchmaking and Market Design, taught by Alvin Roth M.A. ‘73 Ph.D. ‘74, a professor of economics who won the 2012 Nobel Prize in Economic Sciences.

The professors who had to review hundreds of applications to their popular classes developed their own acceptance policies. Roth specifically asked his prospective students to write about something they had experienced related to the course’s subject matter.

Sunday, October 27, 2013

"After a rocky roll-out of a new online computer program, the Common Application said it fixed two big snags that had left students across the country struggling to file applications before early admission deadlines.

The Common Application allows students to apply to multiple schools at once; more than 500 colleges and universities accept it, and it is run by a nonprofit with the same name."

The Common App has some struggling competitors like the Universal College Application; maybe this will be good for them, and will encourage universities to diversify the portals through which they accept admissions.

"The Global Slavery Index 2013 measures the size of the modern slavery problem, country by country. The Index provides a quantitative ranking of 162 countries around the world according to the estimated prevalence of slavery, that is, the estimated percentage of enslaved people in the national population at a point in time. The Global Slavery Index also examines the risk factors and outlines the strength of the government responses in the fight against modern slavery."

Mauritania and Haiti are high per capita, India is big on total numbers

Wednesday, October 23, 2013

But
"“A lot of older women we don’t take — and they’re fabulous, but it’s too hard to match them,” Jill Kelleher said the morning after the party, at the company’s headquarters in Corte Madera, Calif., which was filled with impeccably groomed young female matchmakers (many of whom have marriage- and family-therapy degrees or a background in life coaching, Sunya Andrews said). “We need to find a system to bring in the men.”

Tuesday, October 22, 2013

The American Journal of Transplantation carried this account of China's moves to end its reliance on executed prisoners for transplant organs, in its 24 Sept 2013 issue:

China's transplantation system has undergone a substantial makeover that may end its longstanding reliance on executed prisoners for organ transplants. A new national program for deceased-organ donation based on Chinese cultural and societal norms was announced by Chinese health officials, who say the new system adheres to World Health Organization (WHO) guiding principles and is compliant with the Declaration of Istanbul. Health officials say that with the new program, the use of organs from executed prisoners will be phased out within two years.

The transplant program is based on pilot trials that took place between 2010 and 2012 in 19 of the 31 provincial regions in China, in which organs were obtained from donors after circulatory death.

According to an interview with Haibo Wang, MD, director of the Chinese Organ Transplant Response System Research Center of the Ministry of Health, that appeared in the Bulletin of the World Health Organization in November 2012, “It is not customary—in term of our culture, law and medical practice—to take brain death as the definition of death in China.”[1] For this reason, the new national program will respect Chinese cultural and social values with three categories of donation: 1) organ donation after brain death; 2) organ donation after circulatory death; and 3) organ donation after brain death followed by circulatory death.

The third category “is an important approach that is very unique to China due to its social and cultural perspective regarding death,” says Jiefu Huang, MD, China's former Vice Minister of Health and current head of the Organ Transplant Committee of the National Health and Family Planning Commission (NHF-PC) of the country's Ministry of Health. “The data from the pilot program indicated that China Category in accounted for approaching 50% of overall deceased donors,” says Dr. Huang.

He adds that “another issue is that the final decision making of organ donation rests on family wishes, regardless of the individual's wish before death. This is to respect the Chinese culture, which is very family centered.”

Waitlists, Registries and Allocation

An important aspect of the program is use of a computerized waitlist developed and maintained by the Chinese Organ Transplant Response System based at the University of Hong Kong, which also runs the Chinese Liver Transplant Registry. The kidney registry is based at the 309th Hospital of the People's Liberation Army, the heart registry at The Fuwai Cardiovascular Disease Hospital and the lung registry at Wuxi People's Hospital.

Although the Red Cross Society of China oversaw donation during the pilot trials, there is currently “a battle for the authority to distribute organs,” said Frank Delmonico, MD, president of The Transplantation Society, in a commentary in the July issue of the journalTransplantation.2 He quoted an article published earlier this year in the Journal of Medical Ethics that said the Red Cross would pay families of the deceased for donor organs.[3] Additionally, the Beijing News reported in July that the Red Cross charges hospitals the equivalent of $16,000 US to receive an organ for transplant.[4]

Another option for organ allocation might be one of the registries. Gabriel Danovitch, MD, director of the Kidney and Pancreas Transplant Program at the University of California, Los Angeles, says the international transplant community strongly advocates “the standards of access, transparency, fairness and justice in allocation that is appropriate for a nation as important as China.” He adds, “I sincerely hope that the Chinese Liver Transplant Registry will be given the opportunity to provide access and transparency of allocation for organ transplants within China.”

KEY POINTS

China says the new program adheres to WHO guidelines and Declaration of Istanbul principles.

The program includes three categories of donation, and use of a computerized waitlist.

Transplant professionals have expressed guarded optimism and areas of concern about the new program.

Guarded Optimism or Skepticism?

While Drs. Delmonico and Danovitch have expressed guarded optimism, they note areas of concern. “One is the continued use of donation by execution,” Dr. Danovitch says. “The second is commercialization of organ donation from both deceased- and living-donor sources.” Dr. Delmonico notes that the financial compensation program for deceased-donor organs suggested in the Journal of Medical Ethics article may undermine the trust of families in the determination of death and a societal trust that organs are being distributed fairly.[3]

Three frequent critics of Chinese transplantation say they remain skeptical. Torsten Trey, MD, PhD, co-editor of State Organs: Transplant Abuse in China, and executive director of Doctors Against Forced Organ Harvesting, says that “with the continuous lack of transparency, the new program is as vague as the Chinese Medical Association pledge to the World Medical Association in 2007,” in which China agreed to end organ sourcing from prisoners. Dr. Trey says he's concerned that “prisoners of conscience, in particular unjustly detained Falun Gong practitioners, are forcibly enrolled into the organ donation program. In order to meet international standards, openness to scrutiny is indispensable. Chinese officials often speak of ending China's reliance on prisoners, yet ending reliance—defined (by them) as less than 50%—does not guarantee a complete end.”

David Kilgour, co-author with David Matas of the 2007 report Bloody Harvest: Revised Report into Allegations of Organ Harvesting of Falun Gong Practitioners in China, is also skeptical. He says he doesn't believe China will phase out the use of organs from executed prisoners in the next two years. “The party-state in Beijing knows that governments, legislators, medical professionals and ordinary people across the world are increasingly aware of its inhuman organ pillaging, mainly from Falun Gong prisoners of conscience in forced labor camps, and thus wants to create for the naive the impression that trafficking in organs will soon end,” he says. “All persons of good will wish it would, but it has now gone on since 2001 and still shows no sign of ending.”

Matas says, “I can't predict the future. I'm skeptical for a number of reasons. One is that they are complaining about cultural inhibitions. But this has never been an issue for anything else with the Communists.” He adds, “Will the numbers in the new system ever be sufficient to replace the numbers they are getting from prisoners? It's not clear. I don't think we should take the assurances of the Chinese government that everything is going to be fine and just give us time. I don't think that's an acceptable answer.”

In China, Dr. Huang says “the success of the new deceased organ donation program is the key to end China's reliance on prisoners' organs.” After the pilot trials, “many hospitals decided to abandon the practice of prisoner organ use,” he adds. “The capacity of the new deceased-organ donation is far beyond the prisoner organs and certainly will ease the donor shortage if we can build an effective OPO [organ procurement organization] system in a relatively short time.”

International Forums

A step toward that development took place in May with the First Chinese Organ Procurement Organization International Forum, held in Shenzhen, China. It was announced that the National Italian Transplant Center will help China build and maintain its national organ distribution and safety monitoring system for donors and recipients, as well as provide training on advanced organ donation practices used in the European Union. A five-year cooperative agreement with the Spanish Transplant Procurement Management and Donation and Transplantation Institute will include training programs with Chinese medical staff in China and overseas.

“In May 2014, one year after the kickoff meeting of the new deceased donor program,” Dr. Huang says, “NHFPC is going to host an international conference to create a platform for international and Chinese transplant communities to exchange knowledge from their own experience and, more importantly, work together to review and improve the design of the new deceased-organ donation program.”

Monday, October 21, 2013

"Commercial surrogacy is estimated to be worth more than $1bn a year in India. While pregnant, some surrogate mothers live in dormitories - which critics call baby factories. They give childless couples the family they have longed for, but what is it like for the women who carry someone else's child for money?"

Sunday, October 20, 2013

How dead do you have to be to be a deceased organ donor, and how dead can you be? Deceased donation of organs for transplantation stretches definitions, because you can't be so very dead that your organs are dead too.

Two recent papers in the New England Journal of Medicine raise this uncomfortable question...

The ethics of organ transplantation have been premised on “the dead-donor rule” (DDR), which states that vital organs should be taken only from persons who are dead. Yet it is not obvious why certain living patients, such as those who are near death but on life support, should not be allowed to donate their organs, if doing so would benefit others and be consistent with their own interests.

The increasing disproportion between the supply of donor organs and the demand for transplants as well as the tragic deaths of patients awaiting organs have encouraged the development of creative solutions to increase the donor supply. In the domain of donation from deceased donors, the protocols for organ donation after the circulatory determination of death (DCDD) have been one such response. Most U.S. organ-procurement organizations have seen organs from DCDD protocols account for a growing percentage of all organs donated from deceased donors (see graphOrgan Donation in the United States by Donor Status, 2002–2011.). In England, DCDD organs currently constitute a greater percentage than organs donated after the determination of death by brain criteria (“donation after the brain determination of death,” or DBDD).

Another innovative strategy is the kidney-donation protocol recently proposed by Paul Morrissey of Brown University.1 This protocol permits a lawful surrogate decision maker for a patient with a severe, irreversible brain injury (but who is not “brain dead”) to authorize withdrawal of life-sustaining treatment and premortem donation of both kidneys. Whereas DCDD protocols entail removal of organs after the cessation of life-sustaining therapy and the subsequent declaration of death, the Morrissey protocol provides for procuring organs while the patient remains alive. Life-sustaining treatment is withdrawn after the donation has been accomplished. The patient dies of the respiratory complications of the original brain injury, which is fatal in the absence of life-sustaining treatment.

Saturday, October 19, 2013

Chris Masse alerts me to the interesting site Ads of the World, and points to some of the ads being used to promote kidney donation in Brazil. There's a superhero series that includes Captain America and Spiderman...

And here's the prospective account of the talk I should try to give...

In addition to Kearns and Vohra, the launch event will feature talks by Eduardo Glandt, the Nemirovsky Family Dean of the School of Engineering and Applied Science, and by Alvin E. Roth of Stanford University, who shared in the 2012 Nobel Prize in Economic Sciences.

Roth’s Nobel-winning work was on a theory for finding mutually beneficial matches between nodes in complex networks. The theory’s applications include the process medical students use to apply for residencies, as well as a program for finding compatible donors and recipients for kidney transplants.

“We’re planning on funding research projects that, in addition to being scientifically stellar, have some chance of doing social good,” Kearns said. “That’s one of the reasons Roth’s talk is perfect for this launch: network science can show which kidney is compatible with each recipient, and it needs to draw on algorithms, networks and big data sets, but, at the end of the day, this was a research project that saved people’s lives.”

"A handful of technology companies from Knack.it Corp. to Evolv Inc. are ... developing video games and online questionnaires that measure personality attributes in a job applicant. Based on patterns of how a company’s best performers responded in these assessments, the software estimates a candidate’s suitability to be everything from a warehouse worker to an investment bank analyst...."“People are our biggest resource, and right now a lot of them are mismatched,” said [Erik] Brynjolfsson, who specializes in research on information technology and productivity and is an advisor to Knack. “If you put the right kind of person in the right task, it’s good for that person and it’s good for the company.”..."“You have this enormous pool of people that’s being missed because of the way the entire industry goes after the same kinds of people, asking, did you go to Stanford, did you work at this company?” said Erik Juhl, head of talent at Vungle Inc., a San Francisco-based video advertising startup, and formerly a recruiter at Google Inc. and LinkedIn Corp. “You miss what you’re looking for, which is -- what is this person going to bring to the table?”

Wednesday, October 16, 2013

"Ohio State University Professors Katherine Coffman and Lucas Coffman and Boston University School of Management Professor Keith Marzilli Ericson used a survey research method known as "veiled" reporting to test an array of statements on hot-button issues such as same-sex marriage, homophobic beliefs, and history of same-sex experiences. Unlike traditional anonymous online-survey methods designed to elicit true answers on stigmatized beliefs or practices, this method groups questions so that respondents don't have to answer them directly.

For example, in a normal survey, a person would be asked to answer yes or no about a statement. But in veiled reporting, statements like "I consider myself a heterosexual" are grouped with a bunch of statements like "I remember where I was the day of the Challenger space shuttle disaster," and respondents are asked to say how many statements in the group are true, without having to specify which ones they are saying yes to. A gap between the responses of a control group answering directly and those answering through the veiled-questioning system has been shown to exist for questions where there is a "social desirability bias"—which is to say, where people are inclined to give what they think is the socially acceptable answer."

Abstract: We utilize operations research and market design frameworks to improve the e ectiveness of a recommender system for children in state custody and prospective adoptive families, and describe the implementation of changes to the Pennsylvania Adoption Exchange (PAE). The purpose of PAE is to nd permanent families for hard-to-place children in state custody, and it provides match recommendations to over 200 children each year. After describing PAE's operation, we use data provided by PAE to analyze the relationship between child attributes and adoption outcomes. With the primary objective of improving adoption outcomes, our recommendations cover the information that PAE collects to make recommendations, the decision rules that produce child-family match suggestions, and the interactions between PAE and system participants. We demonstrate the value of improved information about families and children using a discrete-event simulation of PAE. As a result of our collaboration, PAE has begun to collect new information from families and children to better predict match success, to use a spreadsheet tool that provides a more nuanced comparison of family preferences and child attributes, and to change the match recommendation process to reduce strategic manipulation by families. A survey of child case workers in Pennsylvania and interviews with PAE managers guided these changes. Insights from this project are relevant to other adoption exchanges, as well as the placement of children in foster care.
*************************************

Others will write more expertly than I about their work on asset prices, and about finance and behavioral finance. And journalists will be glad to have economics laureates who do something that journalists and the public think that economists do (in contrast to last year's laureates who did something further from the popular conception of economics).

Sunday, October 13, 2013

One of the funnier post-Nobel phenomena, aside from the attention of journalists, is the attention of artists. The most interesting of those whom I have interacted with is photographer Volker Steger, who in collaboration with the Landau organization has created a series of photo/interviews consisting of panoramic portraits of the places where Laureates work, together with links to embedded interviews, some just audio, and some video: NOBEL LABS 360° An Interactive Multimedia Project.

I haven't fully figured out how to navigate the site, but you can let the panorama rotate slowly, or you can navigate to parts of it by experimenting with your mouse...if you click on the link called "Introducing Alvin Roth" you can see a video of me working at and walking on (and talking about) my treadmill desk...and if you explore more you can find a nice shot that includes Rodin's Burghers of Callais on the Stanford campus.

Tomorrow I will graduate from being the most recent Economics laureate to a more emeritus status, and I'm looking forward to a few fewer distractions, although some of them have been quite fun.

Friday, October 11, 2013

"EU laws entitle women in the 28-country bloc to at least 14 weeks of paid maternity leave, although many states offer longer leave than that.

"The laws on surrogacy, by contrast, are much less harmonized. Eight EU member states, among them Germany, France, Italy and Spain, prohibit women from carrying another woman's child altogether. Those nations say they fear the practice could lead to the exploitation of women in financial difficulty or create emotional problems for surrogate mothers who give up the child they carried to birth.

"Other European states prohibit payments that go beyond compensation for medical expenses or restrict the use of fertility treatments or egg donation in surrogacy arrangements.

"In the U.S., laws on surrogacy also vary from state to state, with some placing limits on how much money surrogate mothers can be paid. Since there's no federal right to paid maternity leave, it's generally up to employers to design their own policies. The federal Family Medical Leave Act allows workers—men and women—to take up to 12 weeks of unpaid leave to take care of a relative, provided the company they work for has at least 50 employees.

"Despite the limitations, surrogacy is becoming increasingly popular in Europe. Many childless couples look to other countries, such as Ukraine, India or the U.S.— to find surrogate mothers."

Thursday, October 10, 2013

Controversy about whether there should be horse slaughterhouses in the United States has made the news because of controversy between American Indian groups whose treaty lands are overrun by feral horses, and horse protection organizations that include actors who have played American Indian roles in films: On Fate of Wild Horses, Stars and Indians Spar

"Free-roaming horses cost the Navajos $200,000 a year in damage to property and range, said Ben Shelly, the Navajo president. There is a gap between reality and romance when, he said, “outsiders” like Mr. Redford — who counts gunslinger, sheriff’s deputy and horse whisperer among his movie roles — interpret the struggles of American Indians.
...
"The horses, tens of thousands of them, are at the center of a passionate, politicized dispute playing out in court, in Congress and even within tribes across the West about whether federal authorities should sanction their slaughtering to thin the herds. The practice has never been banned, but stopped when money for inspections was cut from the federal budget.

"In Navajo territory, parched by years of unrelenting drought and beset by poverty, one feral horse consumes 5 gallons of water and 18 pounds of forage a day — sometimes the water and food a family had bought for itself and its cattle.

"According to the latest estimates, there are 75,000 feral and wild horses in the nation, and the numbers are growing, Mr. Shelly said. They have no owners, and many of them are believed to be native to the West. The tribes say they must find an efficient way of reducing the population. Although it is common to shoot old and frail horses — and more merciful than a ride to the slaughterhouse — there are too many of them to be dealt with, and there is some money in rounding them up and selling them at auction.
...
"The United States has never fostered a market for horse meat, a dietary staple in places like Belgium, China and Kazakhstan. It does have a history of horse slaughtering, though; at one point, there were more than 10 such slaughterhouses in the country. The last three, one in Illinois and two in Texas, closed in 2007, after Congress banned the use of federal money for salaries for personnel whose job was to inspect the horses and the facilities where they would be slaughtered. (One thing inspectors look for is evidence of drug use on the horses, not uncommon among those once used for racing.)

"In their last year, the three plants slaughtered a total of 30,000 horses for human consumption and shipped an additional 78,000 for slaughter in Canada and Mexico, according to statistics by United States and Canadian authorities. Congress’s subsequent unwillingness to finance inspections made slaughtered horse meat ineligible for the seal of inspection it needs to be commercially sold, effectively ending the practice.

"Wayne Pacelle, the president of the Humane Society of the United States, a lead plaintiff in the lawsuit and one of the groups lobbying Congress to end horse slaughter, said its efforts were focused on preventing the killing of horses for human consumption “to avoid creating an industry that would turn horses into a global food commodity.”

Wednesday, October 9, 2013

If you were a Silk Road customer, you'll have to find another online drug market: F.B.I. Seizes Silk Road, an Online Drug Market, and Makes Arrest. But it sounds like while the organizer was arrested (after soliciting a murder for hire) the anonymity of transactions may have allowed many of the customers to escape detection.

"The Silk Road marketplace is available through Tor, a popular tool for maintaining anonymity online. Bitcoin, a virtual currency, is used for transactions. The identities of sellers are not known to the buyers. About $1.2 million in sales were conducted a month in early 2012, according to a study by an assistant professor at Carnegie Mellon University, Nicolas Christin.

"The arrest is part of the latest push by federal authorities to police the anonymous marketplaces that have flourished as a result of virtual currencies and software meant to help users browse the Web anonymously. In recent months, federal authorities charged seven people believed to be linked to Liberty Reserve, another virtual currency, which prosecutors described as a $6 billion money-laundering operation that facilitated a black market for everything from stolen identities to child pornography.

"One recent study found that a broad range of drugs, including ecstasy, LSD and heroin, were available on Silk Road, but that marijuana was the most popular item offered for sale. Books and erotica are also sold.

NBER Working Paper No. 19417Issued in September 2013NBER Program(s): APCF

Many financial markets have recently become subject to new regulations requiring transparency. This paper studies how mandatory transparency affects trading in the corporate bond market. In July 2002, TRACE began requiring the public dissemination of post-trade price and volume information for corporate bonds. Dissemination took place in Phases, with actively traded, investment grade bonds becoming transparent before thinly traded, high-yield bonds. Using new data and a differences-in-differences research design, we find that transparency causes a significant decrease in price dispersion for all bonds and a significant decrease in trading activity for some categories of bonds. The largest decrease in daily price standard deviation, 24.7%, and the largest decrease in trading activity, 41.3%, occurs for bonds in the final Phase, which consisted primarily of high-yield bonds. These results indicate that mandated transparency may help some investors and dealers through a decline in price dispersion, while harming others through a reduction in trading activity.

NBER Working Paper No. 19419Issued in September 2013NBER Program(s): IOPR

In this paper, we explore the hypothesis that an important force behind the collapse in advertising revenue experienced by newspapers over the past decade is the greater consumer switching facilitated by online consumption of news. We introduce a model of the market for advertising on news media outlets whereby news outlets are modeled as competing two-sided platforms bringing together heterogeneous, partially multi-homing consumers with advertisers with heterogeneous valuations for reaching consumers. A key feature of our model is that the multi-homing behavior of the advertisers is determined endogenously. The presence of switching consumers means that, in the absence of perfect technologies for tracking the ads seen by consumers, advertisers purchase wasted impressions: they reach the same consumer too many times. This has subtle effects on the equilibrium outcomes in the advertising market. One consequence is that multi-homing on the part of advertisers is heterogeneous: high-value advertisers multi-home, while low- value advertisers single-home. We characterize the impact of greater consumer switching on outlet profits as well as the impact of technologies that track consumers both within and across outlets on those profits. Somewhat surprisingly, superior tracking technologies may not always increase outlet profits, even when they increase efficiency. In extensions to the baseline model, we show that when outlets that show few or ineffective ads (e.g. blogs) attract readers from traditional outlets, the losses are at least partially offset by an increase in ad prices. Introducing a paywall does not just diminish readership, but it furthermore reduce advertising prices (and leads to increases in advertising prices on competing outlets).

NBER Working Paper No. 19433Issued in September 2013NBER Program(s): AGLSPE

What can we, as users of microdata, formally guarantee to the individuals (or firms) in our dataset, regarding their privacy? We retell a few stories, well-known in data-privacy circles, of failed anonymization attempts in publicly released datasets. We then provide a mostly informal introduction to several ideas from the literature on differential privacy, an active literature in computer science that studies formal approaches to preserving the privacy of individuals in statistical databases. We apply some of its insights to situations routinely faced by applied economists, emphasizing big-data contexts.

Accommodating couples has been a long-standing issue in the design of centralized labor market clearinghouses for doctors and psychologists, because couples view pairs of jobs as complements. A stable matching may not exist when couples are present. This article’s main result is that a stable matching exists when there are relatively few couples and preference lists are sufﬁciently
short relative to market size. We also discuss incentives in markets with couples. We relate these theoretical results to the job market for psychologists, in which stable matchings exist for all years of the data, despite the presence of couples.